Make WorkerScriptLoader back to RefCounted class

Source/core/workers/InProcessWorkerBase.cpp

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "core/workers/InProcessWorkerBase.h"
 
 #include "bindings/core/v8/ExceptionState.h"
 #include "core/events/MessageEvent.h"
 #include "core/fetch/ResourceFetcher.h"
@@ skipping 33 matching lines @@
 }
 
 bool InProcessWorkerBase::initialize(ExecutionContext* context, const String& url, ExceptionState& exceptionState)
 {
     suspendIfNeeded();
 
     KURL scriptURL = resolveURL(url, exceptionState);
     if (scriptURL.isEmpty())
         return false;
 
-    m_scriptLoader = adoptPtr(new WorkerScriptLoader());
+    m_scriptLoader = WorkerScriptLoader::create();
     m_scriptLoader->loadAsynchronously(
         *context,
         scriptURL,
         DenyCrossOriginRequests,
         bind(&InProcessWorkerBase::onResponse, this),
         bind(&InProcessWorkerBase::onFinished, this));
 
     m_contextProxy = createWorkerGlobalScopeProxy(context);
 
     return true;
@@ skipping 44 matching lines @@
     m_scriptLoader = nullptr;
 }
 
 DEFINE_TRACE(InProcessWorkerBase)
 {
     visitor->trace(m_contentSecurityPolicy);
     AbstractWorker::trace(visitor);
 }
 
 } // namespace blink